Donald Trump won in 2016 by outlasting 17 candidates he was able to stick with nasty, unflattering, but memorable labels. “Lyin’ Ted.” “Little Marco.” “Low Energy Jeb.” He picked them apart one at a time while they were helping him along by knocking each other off, so by the convention, Trump was the only one left standing.

And now the Democrats are in danger of doing the same thing.

John Madden, football coach and commentator, said that when a team has two starting quarterbacks, they don’t really have one. Donald Trump knows that game and it won for him in 2016. Unless the Democrats narrow the field early they are doomed.

Politics is a simple game: you win by getting the most votes. And because this is not a national election, but 51 state elections, they must be the “right” votes. That’s why Hillary got nearly three million more votes, but Donald Trump is president.

The pundits say the Dems must settle on an approach. But if they move too far left they will lose the center and Independents. Choose a less radical path and progressives may grumble but they will go along because they are aching to vote against Trump. Democrats need a candidate who will capture the most votes in the right places, so the question comes down to identifying who will appeal to more Americans across the board.

Politico recently reported that “potential 2020 presidential candidates have been lining up to take on Donald Trump and the GOP, creating one of the most crowded fields in memory.” They identified 35 contenders, From Joe Biden and Hillary Clinton to outsiders like Oprah and Michael Avenatti. Granted, some may just be running for the VP slot, but it’s still a crowded field. (See https://www.politico.com/2020candidates for their list.)

Twenty percent of the Democrats in The Senate are running. Four more former senators are in the mix as are seven Congressmen and women, seven governors, four current or former mayors and seven ambitious celebrity outsiders who figure that if Donald could do it, well . . .

Some newcomers like Beto O’Rourke and Cory Booker are charismatic, but are they ready for the national stage? Joe Biden is appealing but may be past his “sell by” date. Bernie is even older. Both are energetic and maybe 75 is the new 60.

Perhaps the time is right for a governor or mayor to step up. These are people with real-world governing experience. They have won (and lost) elections and learned how to appeal to different kinds of voters. And they have had to work with fractious, combative and bipartisan legislatures.

Here are a few suggestions that make sense to me:

Mike Bloomberg. Mayor of the most diverse city, New York, successful in business and government, has a good public profile, is virulently anti-gun (a double-edged sword), and presents as very level-headed.

Governors. Montana’s Steve Bullock who was elected as a Democrat while Trump won the state with 70 percent of the vote. Or John Hickenlooper, former Denver mayor and a centrist, business-oriented current governor of Colorado.

And here’s something radical that just might work.

Joe Biden could run as a one-term president, with a charismatic VP candidate gaining four years of experience and visibility, the way Obama did with Biden. Who might it be? Cory Booker? Beto O’Rourke? Or, since there is likely to be a strong push for a woman on the ticket, Kamala Harris, Elizabeth Warren or Kirsten Gillibrand.

The 2020 presidential election is the Dems’ to win or lose. But unless they dramatically narrow the field to just two or three, they — and we — risk going through the same debacle the GOP did in 2015-16.

And all bets are off if, God forbid, Hillary decides to muck things up.